Method for producing synthetic precious stones



Patented Nov. 2, 1926.

PATENT OFFICE.

o'r'ro RUFF, F BRESLAU, GERMANY.

METHOD FOR PRODUCING- SYNTHE'IIG PRECIOUS STONES.

No Drawing. Application filed February 2, 1923, Serial No. 616,616, and in Germany March 15, 1922.

The processfor melting powdered argillac'eous earths or powdered mixtures of clay and metals or the oxides thereof in a vertically arranged oXy-hydrogen burner into synthetic precious stones has been specified by Verneuil in the Annales of Chemistry and Physics, Serial Number 8, Tome 3 of the "year 1904 on page 20 and the following. In

this gazette also a note maybe found-on page 37 according to which the drop, generated in the said oxy-hydrogen burner, is kept in continual revolution.

It is there stated in effect, It is possible, by giving to the support for the melting drops, a rotary motion, to render less necessary the vertical position of the flame, but since after several trials it was made possibleto suitably adjust the blast flame and the furnace to each other, I have not followed out the several f experiments which I had undertaken, to realize this rotation of the support, since the. latter very much complicates the entire device.

In the German Patent 284,258 a process has been specified, according to which the 1 pin supporting the melting drop, is revolved in such a manner, that the axis of the burner and of the drop and pin are lying in the same straight line.

Now it has been found, that if the melting drop, having some mm. in diameter, is "revolved at a speed of less than 60 revolutions per minute, it is not necessary and also not advantageous to adjust the several parts,

of the stove of Verneuil. The powder dropping from the flame into the drop is more easily molten, if the longitudinal axis of the drop and the revolving shaft of the pin are somewhat located aside, so that the powder,

is not accurately fed to the centre of the drop but to one side thereof. The object of the present invention being the said manner of displacement.

Further it has been found advantageous for compensating the tensions in the drop to extinguish the flame of the burner after the finish of the drop, at is is the case in the German Patent 284,258 but to diminish the volume of the flame by and by to stop therevolving of the pin but after extinguishing the oxy-hydrogenburner.

I claim: i

1. A process for the manufacture of synthetic jewel-stones, characterized by smelting mixtures of argillaceous earths and metals or oxides of metals in a downwardly projected blow pipe flame, in such a way, a that the melted and restifl'ened drop, after attaining a diameter of some millimeters, is rotated, with the longitudinal axis of the drop and the axis of the rotation of the pin,

which carries the drop, being a little out of. line with the axis of the flame of th blow-pi'pe-burne'r.

2. A process for the manufacture of syn- 55 thetic jewel-stones, characterized by a blowpipe-burner, and that the finished drop is cooled down quite slowly bythe practice of diminishing slowly the size of the flame of the burner, whilst continuing the rotation of the drop, until the flame is extinguished completely. In testimony whereof I have aflixed my signature.

DR.- oTTo RUFF. 

